This invention relates generally to cartridges for use in audio-visual equipment, and more particularly to a cartridge carrying both picture film and audio tape.
Equipment for frame by frame visual display of pictorial information appearing on reels of picture film or on film strip are widely used to convey information to groups such as sales meetings, classes of students, lecture groups, etc. Generally this pictorial information is presented in connection with a verbal commentary which includes an explanation and discussion of the information contained in the frames. This information can be presented by a lecturer or by use of an audio tape recorder. The live delivery of the explanatory information by a lecturer has the obvious limitation of requiring someone who is deeply familiar with the subject matter to make the presentation.
The use of tape recorded comments overcomes this limitation to a certain extent but still the operator must have a close familiarity with the subject matter so that he is able to assemble the associated film and audio tape mediums and to insure that the audio-commentary is correctly synchronized with the successive frames of visual information on the film. Since there is generally no way provided for indicating which of the series of frames of pictorial information is being projected at any time, this problem of synchronization requires continuous attention on the part of the operator.
The film medium used in audio-visual equipment is generally either 8, 16 or 35mm film. The 35mm film medium provides a satisfactorily large picture frame area but has the disadvantages of requiring a rather large and bulky film handling mechanism and of being rather expensive because of the large size of the film. The 8 and 16mm films allow for a more compact film handling medium but have the disadvantage of having an extremely small picture frame area which results in a rather poor definition in the projected image.
Presently available film cartridges are rather complex in construction and they are generally not suitable for use with reels of film and with film strip. When used with film strip the danger exists with presently available film handling cartridges suitable for reel to reel film that, especially when the frame being projected is close to the leading or trailing edges of the film strip, the film will be transported in an improper manner and, as a result become damaged.